An Unusual Hole in Mars
12.06.2017

What created this unusual hole in Mars? Actually, there are numerous holes pictured in this Swiss cheese-like landscape, with all-but-one of them showing a dusty, dark, Martian terrain beneath evaporating, light, carbon-dioxide ice. The most unusual hole is on the upper right, spans about 100-meters, and seems to punch through to a lower level.

A Solar Prominence Eruption from SDO
26.05.2019

One of the most spectacular solar sights is an erupting prominence. In 2011, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressively large prominence erupting from the surface. The dramatic explosion was captured in ultraviolet light in the featured time lapse video covering 90 minutes, where a new frame was taken every 24 seconds.

The Annotated Galactic Center
27.09.2019

The center of our Milky Way galaxy can be found some 26,000 light-years away toward the constellation Sagittarius. Even on a dark night, you can't really see it though. Gaze in that direction, and your sight-line is quickly obscured by intervening interstellar dust.

Spiral Galaxies Spinning Super Fast
5.11.2019

Why are these galaxies spinning so fast? If you estimated each spiral's mass by how much light it emits, their fast rotations should break them apart. The leading hypothesis as to why these galaxies don't break apart is dark matter -- mass so dark we can't see it.

Analemma of the Moon
7.05.2020

An analemma is that figure-8 curve you get when you mark the position of the Sun at the same time each day for one year. But the trick to imaging an analemma of the Moon is to wait bit longer.

A 10 000 Kilometer Galactic Bridge
3.06.2022

With this creative astro-collaboration you can follow the plane of our Milky Way Galaxy as it bridges northern and southern hemisphere skies. To construct the expansive composite nightscape, skies over Observatorio El Sauce...

Supernumerary Rainbows over New Jersey
27.11.2022

Yes, but can your rainbow do this? After the remnants of Hurricane Florence passed over the Jersey Shore, New Jersey, USA in 2018, the Sun came out in one direction but something quite unusual appeared in the opposite direction: a hall of rainbows.

APOD: 2025 April 9 Б HH 49: Interstellar Jet from Webb
9.04.2025

What's at the tip of this interstellar jet? First let's consider the jet: it is being expelled by a star system just forming and is cataloged as Herbig-Haro 49 (HH 49). The star system expelling this jet is not visible -- it is off to the lower right.

Helios Helium
20.01.2001

This image of the active Sun was made using ultraviolet light emitted by ionized Helium atoms in the Solar chromosphere. Helium was first discovered in the Sun in 1868, its name fittingly derived from from the Greek word Helios, meaning Sun. Credit for the discovery goes to astronomer Joseph Norman Lockyer (born May 17, 1836).

A Quasar-Galaxy Collision?
22.10.1995

In 1963 astronomers were astounded to discover that certain faint, star-like objects have very large redshifts. The large redshifts imply that these objects, now known as quasars (QUASi-stellAR objects), lie near the edge of the observable Universe.